This invention relates in general to automatic transmissions, such as those that are commonly used in the drive trains systems of many automotive and light truck vehicles. In particular, this invention relates to a universal wiring harness that is capable of providing electrical connections between various devices contained within a variety of different automatic transmission structures.
In most vehicles, a transmission is provided in the drive train between the engine and the driven wheels. As is well known, the transmission includes a housing containing an input shaft, an output shaft, and a plurality of gears that can be selectively connected between the input shaft and the output shaft. By controlling the connection of the gears between the input shaft and the output shaft, various forward and reverse gear ratios can be obtained to provide smooth and efficient operation of the vehicle.
In many automatic transmissions, the connection of the gears between the input shaft and the output shaft is controlled by a hydraulic control system that operates a plurality of mechanical clutches. Typically, the hydraulic control system includes a pump that provides pressurized transmission fluid to operate the clutches so as to connect certain ones of the gears contained within the transmission between the input shaft and the output shaft. This is accomplished by providing one or more fluid valves for each of the clutches. By selectively opening and closing the valves, the pressurized fluid from the pump can be controlled so as to operate the clutches to control which of the gears contained within the transmission are connected between the input shaft and the output shaft.
In many recent model automatic transmissions, the operations of the valves contained are controlled electronically by means of an electronic controller. The electronic controller is connected to a plurality of sensors disposed throughout the transmission. The sensors generate electrical signals that are representative of various operating conditions. In response to such electrical signals, the electronic controller generates electrical signals to a plurality of solenoids. The solenoids are connected to operated the various valves contained within the transmission in response to the electrical signals generated by the electronic controller. Thus, as the solenoids are turned on and off by the electronic controller, the various valves are opened and closed, thereby controlling the operations of the clutches and the transmission as a whole.
In such an electronic control system, a plurality of electrical conductors are usually provided to connect the electronic controller to the various sensors, solenoids, and other electrical devices contained within the transmission. Each of the electrical conductors usually includes a length of insulated wire having terminals connected to the ends thereof. The terminals are usually contained within connectors that are sized and shaped to mate with corresponding connectors provided on the various sensors, solenoids, and other electrical devices contained within the transmission to facilitate the connections thereto. As is well known, a typical automatic transmission contains a number of such electrical devices, each of which requires an individual connection. To simplify the installation process, it is known to combine a plurality of the individual electrical conductors into a single wiring harness. A wiring harness is a group of electrical conductors that have been packaged together to simplify the handing thereof and, as a result, facilitate the installation process. Typically, the lengths of wire are bundled packaged together within a single protective cover from which the various terminals and connectors extend at the ends thereof.
As is well known, a wide variety of automatic transmissions are manufactured and sold with modern vehicles. Because they are associated with vehicles of varying size and expense, the structures of such automatic transmissions also vary widely. In particular, the number, type, and location of the various electrical components contained differ from one automatic transmission to another. Thus, although a traditional wiring harness has been found to facilitate the various electrical connections that are made within a single automatic transmission structure, a wide variety of such wiring harnesses must be provided to accommodate the varying structures of automatic transmissions that are manufactured. Unfortunately, it has been found that the manufacture of a wide variety of wiring harness structures is costly and inefficient. Thus, it would be desirable to provide an improved wiring harness that is capable of providing quickly and easily providing electrical connections among a plurality of electrical various devices contained within a variety of different automatic transmission structures.
This invention relates to a universal wiring harness that is capable of providing electrical connections to the various electrical components contained within a variety of vehicular automatic transmissions. The wiring harness includes a plurality of electrical conductors that are supported on a relatively rigid support bracket that is shaped in accordance with the basic structure of the transmission such that the electrical conductors are generally directed toward the locations of the various electrical components. The electrical conductors are preferably covered with an electrical insulator that is formed from polytetraflouoroethylene because it provides enhanced resistance to degradation from chemical exposure, heat, penetration (such as from abrasion or cutting), and color fading. A plurality of terminals and connectors are connected to the ends of the electrical conductors so as to facilitate the connections to the various electrical components of the electronic control system. At least some of the terminals and connectors may be adapted to provide alternative electrical connections with some of the components of the transmission, depending upon the particular structure of the transmission. To prevent dirt and other contaminants from entering into the unused terminal, and further to prevent electrical short circuits from occurring, a closure cap can be provided. If desired, the electrical conductors of the two terminal may be spliced together. The provision of multiple terminals and connectors for a single function allows the wiring harness as a whole to be readily adaptable for use with a variety of different transmission structures. As a result, the number of different wire harness structures that is required to be manufactured or maintained in inventory is greatly reduced.
Various objects and advantages of this invention will become apparent to those skilled in the art from the following detailed description of the preferred embodiment, when read in light of the accompanying drawings.